1. Technical Field
This disclosure relates generally to surgical instrumentation and, more particularly, to a method of using a suturing apparatus to place knots during endoscopic or laparoscopic surgical procedures.
2. Background of the Related Art
Endoscopic or laparoscopic procedures are characterized by the use of an elongated cannula structure having a relatively small diameter with a proximal and distal end. The distal end is passed through the surrounding tissue into the body cavity wherein the surgical procedure or examination is to be effected, thus providing a conduit for the insertion of surgical instrumentation. A plurality of cannula structures may be used to allow operation of a variety of instruments simultaneously during a given procedure. For example, one cannula may provide a conduit for an endoscope for vision and illumination within the operative cavity while the other cannulas may provide conduits for control of specialized surgical instruments designed for performing specific procedural functions.
Many endoscopic surgical procedures call for placing stitches through tissue, a tedious procedure traditionally performed using endoscopic graspers to manipulate a needle and suture. Endoscopic suturing presents a particularly challenging task, because it must be accomplished through a port that typically averages between five and ten millimeters.
Improved instruments for facilitating endoscopic suturing are discussed in British Patent Application No. 2260704, published Apr. 28, 1993; U.S. patent application Ser. No. 08/134,145 filed Oct. 8, 1993; and U.S. patent application Ser. No. 08/319,841, filed Oct. 7, 1994. Endoscopic suturing devices such as those described in the foregoing disclosures provide a significant advantage over the traditional method of passing a needle between two endoscopic grasping instruments. However, in order to prevent the suture line from being "pulled out", the suture line must be secured at both ends, and this task poses a challenge. One solution is provided in U.S. application Ser. No. 08/134,145 in the form of suture anchor deployed from the apparatus. That, however, only secures the line of stitching at the beginning of the line. It would be advantageous to provide a method of using an endoscopic suturing instrument to form knots so that the line of stitching may be secured at any point in the stitching process using only the suture material already present in the stitches, i.e., to tie a knot in the suture to secure the suture and tissue.